The general goals of this program are to devise quantitative diagnostic and treatment aids in the management of strabismus. Specific areas include the following: 1) refinement of clinical eye movement recording techniques to improve diagnosis of eye movement disorder; 2) extension of eye movement recording to additional strabismus pattern cases, and coordination of these velocity findings with other clinical measures; 3) a study of the development of pattern of oculomotor control in infancy, especially with reference to infantile esotropia; 4) the application of electromyography to define the pattern of eye movement control both in normal and abnormal disorders. This will be done both in various gaze modes (saccadic, following), and in various gaze positions where data on the human extraocular muscles is scanty or missing. 5) Electronmicroscopy of normal and abnormal human extraocular muscles; and 6) further investigation of the mechanical determinants of extraocular muscle by application of strain gauge measurements in the clinic.